In security and access control applications, video capabilities are an important feature at access points in an individual office or a facility including one or more buildings and at residences. The installation of cameras and display monitors, the addition of new features and the operation of conventional systems is often complicated by the use of various incompatible communications channels required by the individual systems. Managing the configuration of cameras and display monitors which are often remote from one another is complicated in conventional systems. Displaying video streams from sources other than from known sources and cameras directly connected to the monitors is not easily accomplished.
FIG. 1 depicts a conventional security system 10 including an access control system 12 having monitoring station 14. Current security systems use a combination of coax (analog) connected cameras and Internet Protocol (IP) connected cameras and some systems use only IP connected video cameras. The monitoring station 14 is typically a dedicated personal computer running a software application specifically tailored to the security system 10. The correspondence between a physical location and each module 18 is determined by a physical wiring connection at installation time. The security system 10 further includes a separate video system 30. The video monitoring system typically includes a video display 34, a video mixer 36 (also referred to a video multiplexer 36) and a plurality of video cameras 38. The cameras 38, multiplexer 36 and display 34 are generally coupled via coaxial cable (coax). The cameras 38a-38n are typically controlled by the video display 34 over control lines 35a-35n to provide pan, tilt and zoom (PTZ) functions. An optional video tape recorder (VCR) (not shown) or digital video recorder (DVR) is connected to the mixer 36 to provide a temporary storage of images captured by the cameras 38. Conventional systems can also accommodate known networked based IP (or web) cameras 39a-39n. 
The installation of access control, video, and audio devices in conventional systems is complicated by the panel topology and the use of a combination of video cable, and cable wiring which is used to identify a specific device. Other problems associated with point to point wiring include connecting multiple conductors, labeling each of these conductors, and associating each device with a physical location.
Some conventional systems, such as that described in U.S. Pat. No. 6,504,479 attempt to integrate an image based video security system, a burglar alarm system and an access control system to detect the presence of an intrusion onto a site. However, the control, sensor, video, audio, and bi-directional components in these systems do not operate over a common communications channel and are typically integrated through interfaces from each of the separate applications top level management software, rather than through direct interaction between the lower-level components. Control of these systems is directed from a central monitoring center. Newer systems use IP cameras that combine inputs, sound, and video over a common Real-time Transport Protocol (RTP) or Hypertext Transfer Protocol (HTTP) channel over a network.
It would, therefore, be desirable to provide a security system including distributed control, monitoring, audio and video devices operating over a common communications channel which facilitates the interoperability of the display monitors with remote cameras and other video sources. It would be further desirable to reduce the number of installation tasks and simplify the security system installation.